Why the Mona Lisa Became the World's Most Famous Painting
For roughly 350 years it was a respected but not exceptional Renaissance portrait. What made it the most famous painting on Earth happened almost entirely in the 20th century.
Leonardo da Vinci began the Mona Lisa around 1503, working from a small poplar panel, and by most accounts kept refining it for years — possibly continuing to work on it until close to his death in 1519. Art historians generally accept the sitter as Lisa Gherardini, wife of a Florentine cloth merchant, though Leonardo never delivered the finished portrait to the family who likely commissioned it. For roughly the next 350 years, it hung in French royal and then national collections as a well-regarded Renaissance portrait — admired by specialists, but not meaningfully more famous than several other paintings in the Louvre.
The shift happened almost entirely in the 20th century, and the single largest cause is well documented: on 21 August 1911, an Italian handyman named Vincenzo Peruggia, who had worked at the Louvre, hid overnight and walked out the next morning with the painting under his coat. It was missing for over two years. The theft made front-page news across Europe and America — visitors reportedly lined up to view the empty space on the wall where it had hung — and when Peruggia was caught trying to sell it to a Florence art dealer in 1913, the recovery generated a second wave of global press attention.
That publicity never really faded. The painting toured the United States in 1963 and Japan and the USSR in the 1970s, each stop drawing enormous crowds and further press coverage, compounding a reputation that had already outgrown any single quality of the work itself. By the time mass tourism and, later, the internet arrived, the Mona Lisa's fame had become self-reinforcing: it is one of the most reproduced images in art history largely because it had already become one of the most reproduced images in art history.
The Technique Behind the Smile
Part of the painting's pull is a genuine technical achievement, not just its history. Leonardo was the leading practitioner of sfumato, an Italian term meaning roughly 'gone up in smoke' — a way of blending colour so transitions between light and shadow, or between one tone and the next, have no hard edge. Applied to the corners of the mouth, sfumato is why the Mona Lisa's expression seems to shift depending on where a viewer looks: stare directly at her mouth and the eye catches faint downward lines that read as neutral, but shift focus to her eyes or cheeks and the mouth is seen only peripherally, where the blurred shading reads as the hint of a smile. A 2024 study in the journal Scientific Reports examined this shaded region closely and found a similar effect, which the researchers termed an 'ambiguity nuance,' in other Leonardo portraits — meaning the shifting smile is a repeatable technique, not an accident unique to this one painting.
A Painting Everyone Wants to Touch
Fame made the Mona Lisa a target almost as often as it made it an attraction. In the 1950s alone, the painting survived an acid attack on its lower half and a rock thrown by a visitor that chipped paint near the left elbow — the incident that led the Louvre to install its first protective glass. That glass has held: a teacup thrown at the painting in 2009, cake smeared on its case in 2022 by a visitor who faked a disability to get close in a wheelchair, and soup thrown by protesters in 2024 all left the painting itself completely undamaged. The Louvre has upgraded the case twice more since, most recently in 2019, each round of security becoming its own small news story — another instance of the same self-reinforcing fame described above, where an attack on the world's most famous painting generates headlines mostly because of how famous it already is.
The painting, illustrated
Frequently Asked Questions
Why does the Mona Lisa's smile seem to change when you look at it?
It's an effect of Leonardo's sfumato technique — soft, blended shading with no hard edges at the corners of the mouth. Looking directly at the mouth, the eye picks up faint lines that read as neutral; looking slightly away, at the eyes or cheeks, the mouth is seen only peripherally, and the blurred shadow there reads as the hint of a smile.
Has the Mona Lisa ever been damaged?
It survived an acid attack and a thrown rock in the 1950s, which chipped paint near the left elbow and prompted the Louvre to add its first protective glass. Every attack since then — including a thrown teacup, smeared cake, and thrown soup — has left the painting itself undamaged because of that glass.
Who was the real Mona Lisa?
Art historians generally identify the sitter as Lisa Gherardini, the wife of a Florentine cloth merchant, though Leonardo never delivered the finished portrait to the family thought to have commissioned it — he kept working on it, by most accounts, until close to his death in 1519.